When a user interacts with a computer system, the user typically establishes a personal context so that subsequently invoked computer programs operate by default on data specific to the user. The user can establish a context in various ways, for example by entering a user identifier via a keyboard, or by presenting a hardware token such as a smart card which contains a user identifier.
When a user interacts with an Internet Web site, a personal context is often automatically established with reference to a cookie previously stored by the Web site on the user's computer system.
In the process of establishing a personal context, the user is often expected to provide secret or biometric information which is difficult for a potential impostor to obtain or forge. Usually, the secret or biometric information is verified in the context of the identity of the user, rather than being indicative of the identity of the user per se.